EEeevmanu·Mar 27, 2026
In A Faster Alternative to Jqadamritter
fastgron
C++2023–2026
adamritter / fastgron
fastgron
High-performance JSON to GRON (greppable, flattened JSON) converter
7Distinct people
11Mentions
0Explicit recommenders
680GitHub stars
What to know before exploring
What it is
High-performance JSON to GRON (greppable, flattened JSON) converter
GitHub
Where it is used
No documented product use has been verified yet.
What people are saying
No recommendation phrase was found in the indexed comments.
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Also in these discussions
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This week on Hacker News
Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 5:04:57 PM UTC.
No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.
Mentions over time
HN mentions by year11 dated mentions
Observed mentions: 2023-05-28 12:06:40 UTC to 2026-03-27 17:00:02 UTC.
* An incomplete calendar period is marked with an outlined bar. Its count is not directly comparable with a full period.
Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.
View mention counts and date ranges
| Period | Start (UTC) | End (exclusive, UTC) | Mentions | Submissions | Comments |
|---|---|---|---|---|---|
| 2023 | 2023-01-01 00:00:00 UTC | 2024-01-01 00:00:00 UTC | 6 | 1 | 5 |
| 2024 | 2024-01-01 00:00:00 UTC | 2025-01-01 00:00:00 UTC | 1 | 0 | 1 |
| 2025 | 2025-01-01 00:00:00 UTC | 2026-01-01 00:00:00 UTC | 3 | 2 | 1 |
| 2026 (partial) | 2026-01-01 00:00:00 UTC | 2027-01-01 00:00:00 UTC | 1 | 0 | 1 |
What Hacker News says
11 sourcesFastgron High-performance JSON to GRON (greppable, flattened JSON) converter
5 points · Open discussionI'm a long time user of this snippet as well. I discovered fastgron [0] last year and found it convenient for some situations!
[0] https://github.com/adamritter/fastgron
In Jqfmt like gofmt, but for jqFastgron: Make JSON greppable, super fast
6 points · Open discussionI don't really understand what's new here compared to what SIMDJSON supported already.
Anyways, it's the best JSON parser I found (in any language), I implemented fastgron (https://github.com/adamritter/fastgron) on top of it because of the on demand library performance.
One problem with the library was that it needed extra padding at the end of the JSON, so it didn't support streaming / memory mapping.
In On-demand JSON: A better way to parse documents?Thanks, it's a clear bug. I created a new issue for it: https://github.com/adamritter/fastgron/issues/19
In Gron: Make JSON greppableCan you try https://github.com/adamritter/fastgron as a comparision?
In Gron: Make JSON greppableHere's the fastgron printer if you want to compare:
https://github.com/adamritter/fastgron/blob/main/src/print_g...
In Gron: Make JSON greppableI use gron a lot, because I can never remember how to use jq to do anything fancy but can usually make awk work. (I may be unusual in that department, in that I actually like awk)
One warning to note is that gron burns RAM. I've killed 32GB servers working with 15MB JSON files. (I think gron -u is even worse, but my memory is a bit fuzzy here).
https://github.com/adamritter/fastgron as an alternative has been pretty good to me in terms of performance, I think both in speed and RAM usage.
In Gron: Make JSON greppableAnd also https://github.com/adamritter/fastgron that I've just discovered.
In Jaq – A jq clone focused on correctness, speed, and simplicityShow HN: fastgron: A JSON to GRON Converter That's 40 Times Faster Than Gron
Hello HN! I want to introduce fastgron, my new project.
fastgron is a JSON to GRON converter, built to be incredibly fast – it's 40 times faster than Gron. GRON is a tool for making JSON greppable, but it can slow down with larger files. With fastgron, even a 200MB JSON file can be converted in just 1 second.
Key features include streaming conversion for memory efficiency and an optimized path reconstruction for faster operations. It leverages C++ and the simdjson and fast_io libraries for speed.
I welcome all feedback, suggestions, or questions. Thank you!
23 points · Open discussion